Active control of composite box beams using in-plane piezoelectric actuation and structural coupling with optimization

An integrated structures/controls optimization is developed for vibration suppression of a composite box beam with surface bonded piezoelectric actuators. The penalty approach is used to perform the multi-objective hybrid optimization to enhance damping of the first lag, flap, and torsion modes while minimizing control input. The objective functions and constraints include damping ratios, and natural frequencies. The design variables include ply orientations of the box beam walls, and the location and size of the actuators. Two box beam configurations are investigated and the results are compared. In the first, piezoelectric actuators are bonded to the top and bottom surfaces and in the second, actuators are bonded to all four walls for additional in-plane actuation. Optimization results show that significant reductions in control input and tip displacement can be achieved in both cases, however, improved response trends are obtained with in-plane actuation.